Brake



Nov. 9, 1937.

v. w. KLIESRATH BRAKE Filed April 24, 1936 INVENTOR. V/cmQ W AL/[JEATH BY ATTORNEY rangement of the various parts including the inder l6 and the casing 42 is provided with a cation and claim and after a consideration of terial 56. 'Therear end of the casing 42 is sealed my invention;- stem 62 which as shown in Figure 1 is connected Figure 2 is a view in section on an enlarged to the pedal 38. Within the valve 34 this stem scale of the valve shown in Figure 1; and carries slidably mounted-thereon a pair of com- Figure 3 is a view in section on an enlarged pressible sealing disks 64 and 66 which are rescale of the power cylinder shown in Figure l. siliently urged apart by a spring 68. The spring with the intake manifold 26. Thus the intake ment of the stem 62 to the left as seen in Figure 45 Patented Nov. 3, 1937 Q UNlTED STATES PATENT. OFFICE Victor w. Kliesrath. South Bend, Ind., assignor to Bendix Products Corporation, South Bend, Ind., a corporation of Indiana ApplicationApril 24, ia'saserm No. 76,119

1 Claim. (01. 188-152) This invention relates to power operated brakes The valve 34 is controlled by the pedal 38 to conand is disclosed as a 'vacuum power operated nect the rear end of the power cylinder it either brake for an automobile. For operating the with the intake manifold 26 or with theatmosbrake disclosed power is supplied by utilization phere as may be desired or to maintain the rear of the suction available in the intake manifold end of the cylinder l6 isolated from both the of the automobile. intake manifold or the atmosphere.

One of the objects of the invention is the sim- My improved valve is shown more clearly in plification of control arrangement for such a Figure 2 wherein it may be seen that the valve 34 power brake and the provision of a valve which comprises a pair of casings 40 and 42 secured to is simple and economical to manufacture and each other by bolts such-as 44. The casing 40 10 eflicient in use. is provided with a threaded port 45 towhich is A further object of the invention is the arsecured the conduit 32 leading to the power cylvalve and power cylinder so that the power efiithreaded port 46 to which is connected theconciently operates the brakes and so that in the dult 30 leading to the intake manifold 26. The 15 event of failure of the power the brakes may be casing 40 is also provided with ports 48 which applied manually. v connect the interior of the casing with the at- Fuither objects of the invention will be apmosphere by way of an air cleaner 50 including parent after a reading of the subjoined specifla pair of sleeves 52 and 54 and absorbent mathe accompanying drawing in which: i by a plug 58 in which there is threaded a second Figure l is a fragmentary diagrammatic view plug 60 for purposes later to be described.

illustrating the arrangement of the various parts Extending through both of the casings 40 and of a power brake system constructed according to 42 is a movable valve element including a valve It may be seen that I have illustrated in Fig 68 is interposed between a pair of metallic guides 30 ure 1 an automobile provided with wheels Ill, 9. l0 and 12 which in turn contact with the sealing brake operating cross shaft l2 which is connected members 64 and 66 respectively to urge the sealby tension connections l4 with the brakes for ing members apart. For limiting the movement operating the brakes. of the sealing members 54 and 66 and for mov- The brakes are normally operated by power. ing-those members as desired there is secured on 35 A power cylinder 16 is provided with a piston l8 the stem 62 on opposite sides of the sealing memconnected by a piston rod 20 and a tension link bers 64 and 86 a pair of annular rings 14 and I6.

22 with a lever 24 secured to the cross shaft 12. These rings are secured by spring clips 18 and The forward face of the piston 18 is exposed to slipped into grooves in the stem 62. Thus the atmospheric pressure. The rearward face of the ring I4 normally urges the member 64 away 40 piston I8 is at times exposed to atmospheric from its seat on the casinglll and the ring 16' pressure but is also at other times exposed only is adapted at times to urge the sealing member to subatmospheric' pressure developed in the rear 66 away from its seat on the casing 42. The rings end of the cylinder by reason of a connection 14 and 16 are spaced apart so that a slight move manifold is connected with the rear of the cylin- 2 will allow both the sealing member 64 and the der It by conduits 28, 30 and 32. Interposed besealing member to seat to close the valve tween the conduits- 30 and 32 is a valve 34 which against passage of air therethrough in either dicontrols the connection between the intake manirection. A spring I! interposed between the .end I fold and the power cylinder. Also interposed beof the casing. ll and a ring 84 mounted on the 50 tween the conduits 28 and 30 is a pressure control stem 62 similarly to the rings 14 and 16' normally valve 36 by which the maximum suction desirurges the stem toward the right as shown in Figable in the power cylinder I8 is limited and by are 2 so as to unseat the sealing member 64 and means of which the suction available for the to allow the sealing member 66 to rest upon its operation by power is made more nearly uniform. seat. In this position air may flow freely between the rearward end of the cylinder 66 through the conduit 32 into the port so and through the ports 48 to the atmosphere or may return along a similar path from the atmosphere,

thus maintaining the rear end of the power cylinder H5 at atmospheric pressure. The rearward end of the stem 62 is formed with an enlarged portion 86, which in case of failure of the power cylinder to operate the brakes, is adapted to contact with the plug 60. A tension link 88 is connected to the lever 26, and thus the stem 62 through the contact with the plug and through the plug 58 and the link 88 is adapted. to operate the cross shaft H to apply the brakes manually.

The power cylinder I6 is shown more in detail in Figure 3 as is also its piston i8. As shown the cylinder is provided with an extension by which it is connected to the chassis of the automobile and with an opening 92 to which the conduit 32 is connected. The forward end of the cylinder 94 is provided with openings I. which are connected through an air cleaner 98 with the atmosphere.

In the operation of brakes according to this invention, pressure by the operator upon the foot pedal 38 moves my improved valve member to connect the rear of the power cylinder with the intake manifold 26, thus withdrawing air from the rear end of the power cylinderand pressure of the atmosphere acting on the forward face of the piston moves the piston rearwardly, thus exerting tension on the rod II and through the link 22 and the lever 24 rotating the cross shaft I! to apply the brakes. As the brakes are applied. and the shaft l2 rotated, link 8! moves the casing of the valve 34, thus lapping the valve so that the rear end of the power cylinder is cut ofl from the intake manifold suction as well as from the atmosphere. Further movement of the pedal SI is eiiective to again open communication between the intake manifold and the rear end of the cylinder and apply greater pressure to the brakes. Upon the release of the pedal the connection between the intake manifold and' the cylinder is cut oil and a connection is made between the atmosphere and the power cylinder, thus allowing air to flow into the power cylinder and cause the spring 82 and causes the ring 16 to contact with the sealing member 66, thus moving the sealing member from its seat and connecting the opening 46 with the opening 45, thus connecting the intake manifold with the rear end of the cylinder. As the cross shaft I2 is rotated the link 88 is moved to move the casing so that the sealing members 64 and 66 are again spread apart by the aoeaeos spring 68 and the member 66 comes again into contact with its seat. When the sealing member i6 contacts with its seat the rear end of the cylinder 86 is again cut off from both atmosphere and vacuum and the brakes are held in the position at which they are. In the event that greater braking is desired this operation must be continued by additional pressure on the pedal 58 and the resultant continued tension on the stem 62. Upon release of pressure upon the pedal the spring 82 moves the movable valve elements to the position shown in Figureii, thus allowing atmospheric pressure to fill the rear end of the cylinder i6 and release the brake to the extent allowed by the return of the pedal.

It is to be understood that the above-described embodiments of my invention are for the purpose of illustration only and various changes may be made therein without departing from the spirit and scope of the invention.

I claim:

A vacuum power brake system comprising brakes, a power cylinder, connections between the power cylinder and the brakes, means for connecting one end of the power cylinder constantly with the atmosphere, a source of suction, means for at will controlling fluid connection to the other end to the power cylinder to connect said end either to the source of suction or to the atmospheric as desired, said means for controlling the connection to the power cylinder comprising a valve, and said valve comprising a casing formed with a forward end and a rearward end, formed with an opening adjacent to the forward end connected with the atmosphere, formed with an opening adjacent to the rearward end connected with said source of suction, formed with a pair of valve seats interposed between said openings, formed with an opening intermediate said seats arranged to-be connected with said power cylinder, and formed at its forward end with a central bore, and provided with a pair of substantially uniform size valve elements also interposed, a stem extending into said casing through said central bore and provided with an enlargement at its-rearward end and with three annular rings, two of which are arranged at times to contact with said valve elements to move said valve elements from sealing engagement with their associated seats, and connected outside of said casing with a member for operating said stem whereby one or the other said valve elements may be moved from its associated seat or both of said elements may be allowed to rest upon their associated seats, a spring interposed between said their respective seats, a spring interposed be-= tween the forward end'of said casing and said third ring, an air cleaner associated with said atmospheric opening, and a pair of plugs secured within the rearward end of said casing against which-the enlargement of the stem is at times arranged to hear so as to move the casing in either direction as desired.

VICTOR W. ELIESRATE.

valve elements and urging both of them toward 

